Alfonso Soriano is having a resurgent year after his forgettable 2009. On the strength of his seven HRs (and a total of 23 extra-base hits) and a 0.386 OBP, Soriano has an amazing 0.432 wOBA, putting him in the top ten in the league.

Soriano is blasting everything skyward, as his GB% is second lowest in the league at 25%. He has always has always been a fly-ball hitter, but this ground-ball rate is well below his career average of 32%. Ground-ball rate is tied to pitch height, so l looked at Soriano's swing rate by pitch height to see whether there was anything going on.

Nope, it looks like Soriano is swinging at about the same height of pitches, though he is swinging at fewer pitches this year compared to the others in the pitchf/x era. Instead it looks like no matter the pitch height Soriano has, so far this year, hit a lower rate of balls in play on the ground compared to previously. It looks like this is particularly true for pitches up in the zone.

What is making Soriano so successful this year is not that those fly balls are leaving the park at a rate higher than his career average (actually his HR/FB this year is a tad lower than his career average), rather they are dropping in for hits more often. Since 2002 Soriano has a 0.146 BABIP on fly balls (as classified by BIS and courtesy of FanGraphs), but so far this year his BABIP on fly balls has been has been 0.341.

Soriano has 44 non-HR fly balls in 2010 and 15 non-HR fly-ball hits. Had he gotten fly-ball hits at his career rate he would have just six or seven non-HR fly-ball hits. If we take away eight of his singles he ends up with a OBP of 0.331 and a wOBA of 0.389. If we took those eight hits away as five singles and three doubles his wOBA would drop to 0.383. Both still very good, but no longer in the top ten in the league.

Obviously what is done is done and those 15 fly-ball hits are money in the bank for Soriano and the Cubs. But unless you think Soriano can continue to get a hit on a third of his non-HR flyballs, don't think he is going to keep up this torrid pace (and probably not one though he would to begin with). Just another reminder of the fickleness of BABIP. After being on the short-end of the BABIP-luck stick last year Soriano has seen his fortunes flip this year.